1. Field of the Invention
This invention relates generally to multiple computer data transferring and, more particularly, to a system and method using e-mail protocols for a return path for command and control interactivity with outlying receiver sites.
2. Related Art
Large communication networks transmit content data such as audio and video programming over a wide geographical area by satellite broadcast, terrestrial broadcast, cable or Internet. One type of satellite communication system is a point to multipoint configuration wherein transmission equipment at a single, central location, for example a satellite uplink, may send data, control information, audio and video signals to hundreds or even thousands of individual locations multiple receiving stations such as satellite down links and may be geographically positioned over the entire country or any other geographic area. The data and signals from the uplink are transmitted via satellite to the downlinks virtually immediately. These point to multipoint communications networks have a variety of uses such as simultaneously switching audio and video programming for cable television networks, voice communications, sending electronic mail, or controlling equipment at physically remote outposts, as well as many other applications.
It is often necessary to obtain status information for each network device, such as a satellite receiver. This is done for any number of reasons, but primarily for the monitoring of network performance and network maintenance. One presently known method of obtaining status information for network devices includes producing physical printouts at each network device and collecting all printouts in a central location. This is a burdensome and time consuming technique. Another method is to transfer files through the use of user-defined protocols in conjunction with a dedicated server. This technique limits the network size to the quantity of devices that can be serviced by a central control system. Still another method in the arena of satellite communications is to provide extensive hardware at the uplink such that it could receive a significant amount of traffic from a multitude of network devices. This technique is not practical due to the expense of necessary hardware to allow for multiple devices to transmit status information simultaneously.
Additionally, data is often exchanged between the uplink and downlinks that are associated with computers or computer networks using the Transmission Control Protocol/Internet Protocol (TCP/IP). TCP/IP is integrated into the OSI reference model for networks wherein TCP performs the transport layer function and IP performs the network layer function. Because TCP/IP is a part of the normal network software contained within a computer system, direct use of TCP/IP will usually penetrate the firewall established for the computer system. Because of this, most computer systems severely limit the direct use of TCP/IP within their computer systems, except for certain well known applications such as electronic mail, through the use of a firewall.
A firewall is a system or group of systems that enforces an access control policy between two networks. The actual means by which this is accomplished varies widely, but in principle, the firewall can be thought of as a pair of mechanisms: one which exists to block traffic, and the other which exists to permit traffic. Generally, firewalls are configured to protect against unauthenticated interactive logins from the “outside” world. Most firewalls, however, permit email traffic through them, thereby protecting the network against any attacks other than attacks against the email service.
U.S. Pat. No. 5,594,490 to Dawson discloses a system and method for file transfer communication wherein data files are transferred in packet form from a distribution station to a plurality of receiving stations via satellite. If a receiving station detects an error in one of the packets, it requests by modem a retransmission of the particular packet. Dawson, however, does not disclose an easy and reliable means of penetrating a firewall.
U.S. Pat. No. 6,272,549 to Daniel discloses a method for using electronic mail for exchanging application data between computer systems using TCP/IP. This method builds an additional TCP/IP layer on top of an electronic mail system that may communicate between computers and thus penetrates firewalls. It does not disclose interactive communication with broadcast receivers via e-mail.
U.S. Pat. No. 6,415,329 to Gelman et al. discloses a method of communicating over a satellite link using the TCP/IP configuration. In the method, data packets are transferred from a source gateway to a first application, from the first application to a second application, and from the second application to the destination gateway. Gelman also does not disclose an easy and reliable means of penetrating a firewall.
There remains a need in the art for a return transmission path that allows for a multitude of network devices with distributed content data to report status information and reduces firewall impedance.